Few people—if any—enjoy thinking about cancer risk. It’s a scary and emotional topic, especially if it runs in your family. But Dr. Joshua G. Cohen, MD, FACOG, FACS, encourages you to think and talk about cancer with your doctor. Topics to go over could include preventing cancer, understanding cancer risks and making healthy choices to lower your odds (or catch the disease early if you develop it).
This can help you understand that cancer risk isn’t determined by a single factor, like genetics. Even the products we put in our hair every day can affect our health.
“Cancer risk is shaped by many factors, including age, family history, lifestyle and environment,” Dr. Cohen, the medical director of the gynecologic cancer program at City of Hope Orange County, tells Parade. “Everyday products are only one part of that picture, but they still matter because they may contain chemicals that affect hormones, inflammation or how cells grow over time.”
When you have a fuller picture of cancer risk factors, you can take steps to lower your personal chances of developing it. Dr. Cohen shares that regular checkups and preventive screenings, such as mammograms and colonoscopies, are two hallmarks of protecting your health. However, you can also make intentional choices about the types of personal care products we use, such as in our hair.
In fact, based on emerging research, oncologists are begging women to ditch one common hair product, saying data suggest it may contribute to cancer risk. Scroll on for their insights and the research they studied.
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The Common Hair Product You May Want To Stop Using, Oncologists Warn
Oncologists are warning women that chemical relaxers can contain ingredients that could raise cancer risk. “Hair straightening products contain numerous chemicals, and some have been classified as known agents that cause cancer, called carcinogens, such as formaldehyde, phthalates, parabens and bisphenol A (BPA),” states Dr. Ashley Haggerty, MD, a gynecologic oncologist with Hackensack Meridian Riverview Medical Center and Jersey Shore University Medical Center in New Jersey.
Let’s back up for a second. What precisely are chemical relaxers? They’re products or treatments used to straighten hair.
“They are often used on tightly curled or coiled hair and commonly contain strong alkaline chemicals, such as sodium hydroxide in lye relaxers or guanidine hydroxide in no-lye relaxers,” explains Dr. Samilia Obeng-Gyasi, MD, MPH, a breast surgical oncologist at OSUCCC-James. “These chemicals change the protein structure of the hair so that it becomes straighter.”
Black women disproportionately use chemical straighteners. Unfortunately, Dr. Cohen points to research, including a 2023 study of more than 46,000 Black women, suggesting that they are also more likely to develop uterine cancer.
“This data indicates that certain hair relaxers may contribute to the risk of cancer in combination with other aspects of a person’s medical history and lifestyle,” he says.
Dr. Cohen acknowledges the deep-seated and complex reasons why people may use these relaxers. “Hair can be a deeply personal part of one’s identity, culture and self-expression,” he says. “Beauty standards, workplace expectations and cultural pressures have historically influenced their use.”
Still, he notes that more recent evidence, including a 2025 study, suggests a potential link between chemical relaxers and non-Hodgkin lymphoma, pancreatic cancer and thyroid cancer.
Related: Oncologists Are Begging People To Throw Out This Common Kitchen Item
What Happens When You Use Chemical Relaxers
The chemicals in relaxers can straighten hair. But some ingredients are concerning for cancer risk.
“Some chemical straighteners and relaxers may contain or release chemicals of concern, including formaldehyde or formaldehyde-releasing chemicals, phthalates, parabens and other endocrine-disrupting chemicals,” Dr. Cohen notes. “Some of these chemicals can interfere with hormone signaling, including estrogen pathways.”
Uterine cancer can develop if estrogen levels are too high and not balanced by the hormone progesterone, and Dr. Cohen adds that chemicals in relaxers might also contribute to inflammation, oxidative stress or DNA damage over time.
“That’s important because hormones and chronic inflammation can influence how certain cancers develop and grow,” he says. “At the same time, researchers are still trying to determine which ingredients may be most concerning, how much exposure matters and whether certain people may be more vulnerable than others.”
Dr. Obeng-Gyasi echoed these sentiments. “What we do not know is exactly which ingredients, brands, or formulations are most responsible for the possible risk,” she says. “Many studies ask people about general product use, but they do not always capture the exact product, ingredient list, or changes in formulas over time.”
Related: We Asked 3 Oncologists About the Worst Thing You Can Do for Cancer Risk and They All Said the Same Thing
What To Do if You Use Chemical Relaxers
Data suggests that chemical relaxers can contribute to cancer risk, but Dr. Haggerty reminds us that “correlation does not equal causation.” The research isn’t definitive and is evolving. Still, “Best practices would be to decrease or avoid use as much as possible going forward,” she says. “There is no research that has shown a safe dose.”
Dr. Obeng-Gyasi agrees that “more research is needed to determine which products, ingredients, exposure levels, and patterns of use carry the greatest risk.” Still, she says that people who have used relaxers deserve information about the risks, and she advises them to discuss concerns or symptoms with their doctor.
There are also alternatives to chemical relaxers, so you can love your hair and feel more comfortable about your health.
“People who want alternatives should speak with a licensed cosmetologist or hair care specialist about options that fit their hair type and goals,” Dr. Obeng-Gyasi says. “The main benefit is reducing exposure to harsh chemical straighteners. However, alternatives should still be done carefully, because excessive heat, scalp irritation or tight hairstyles can also damage the hair and scalp.”
Up Next:
Related: The One Thing Oncologists Wish People Would Stop Storing in Their Fridge
Sources:
- Dr. Joshua G. Cohen, MD, FACOG, FACS, the medical director of the gynecologic cancer program at City of Hope Orange County
- Dr. Samilia Obeng-Gyasi, MD, MPH, a breast surgical oncologist at OSUCCC-James
- Dr. Ashley Haggerty, MD, a gynecologic oncologist with Hackensack Meridian Riverview Medical Center and Jersey Shore University Medical Center in New Jersey
- Hair relaxer use and risk of uterine cancer in the Black Women’s Health Study. Environmental Research.
- Use of hair straighteners and chemical relaxers and incidence of non-reproductive cancers. Journal of the National Cancer Institute.
